Mark Jenkinson was among the 246 MPs to vote against calls to introduce a cap on how much people pay for social care.
Mr Jenkinson, who represents Workington, was among the 19 Conservative MPs to rebel against the plans, which have attracted major criticsim.
Westmorland and Lonsdale MP Tim Farron also voted against the bill, while Conservatives Simon Fell (Barrow and Furness), Neil Hudson (Penrith and the Border) and John Stevenson (Carlisle) abstained.
Trudy Harrison (Copeland) voted in favour of the bill.
Despite the backbench rebellion, the bill passed in the House of Commons. It now goes forward to the House of Lords.
The bill calls for an £86,000 cap on how much anyone has to pay for social care.
Until last week, people thought financial support from local authorities would count towards that sum.
But under the new clause, the Government has removed local authority money from the calculation, meaning many people will have to pay £86,000 themselves.
Those with assets of less than £20,000 don’t need to pay anything toward their care – up from the current threshold of £14,250.
And those with assets worth up to £100,000 can receive local authority support, up from the current threshold of £23,250.
Many argue that the new proposal could lead to people living in cheaper houses having their assets wiped out.
